Student.c

//2

#include <stdio.h>
#include <stdlib.h>

typedef struct{
    char name[25];
    int reg_no;
    float m1,m2,m3;
    float avg;
}st;

void read(st*p,int n){
    for(int i=0;i<n;i++){
        printf("FOR STUDENT-%d\n",i+1,"___________\n");
        printf("Enter name: ");
        getchar();
        scanf("%[^\n]",(p+i)->name);

        printf("Enter register number: ");
        scanf("%d",&(p+i)->reg_no);

        printf("Enter marks in subject 1: ");
        scanf("%f",&(p+i)->m1);

        printf("Enter marks in subject 2: ");
        scanf("%f",&(p+i)->m2);

        printf("Enter marks in subject 3: ");
        scanf("%f",&(p+i)->m3);
    }
}

void display(st*p,int n){
    printf("%-15s%-15s%-15s%-15s%-15s%-15s\n","NAME","REGISTER NO.","SUB-1","SUB-2","SUB-3","AVG OF BEST TWO MARKS");

    for(int i=0;i<n;i++){
        printf("%-15s%-15d%-15.2f%-15.2f%-15.2f%-15.2f\n",(p+i)->name,(p+i)->reg_no,(p+i)->m1,(p+i)->m2,(p+i)->m3,(p+i)->avg);
    }
}

void average(st*p,int n){
    for(int i=0;i<n;i++){
        float min=(p+i)->m1<(p+i)->m2?((p+i)->m1<(p+i)->m3?(p+i)->m1:(p+i)->m3):((p+i)->m2<(p+i)->m3?(p+i)->m2:(p+i)->m3);
        (p+i)->avg=(p+i)->m1+(p+i)->m2+(p+i)->m3-min;
        (p+i)->avg/=2;
    }
    printf("Calculation Complete...\n");
}

void sort(st*p,int n){
    for(int i=0;i<n-1;i++){
        for(int j=0;j<n-1-i;j++){
            if((p+j)->reg_no>(p+j+1)->reg_no){
                st temp=*(p+j);
                *(p+j)=*(p+j+1);
                *(p+j+1)=temp;
            }
        }
    }
    printf("Sorted...\n");
}

void main(){
    int n,ch;
    printf("Enter the total number of students: ");
    scanf("%d",&n);
    st*p=(st*)calloc(n,sizeof(st));

    printf("ALL MARKS TO BE ENTERED OUT OF 100 ONLY\n");
    for(;;){
        printf("\nENTER:\n1. To read\n2. To display\n3. To calculate the average of best two marks of each student\n4. To sort students based on reg no\n0.To EXIT\nEnter your choice: ");
        scanf("%d",&ch);
        switch(ch){
            case 1:
            read(p,n);
            break;

            case 2:
            display(p,n);
            break;

            case 3:
            average(p,n);
            break;

            case 4:
            sort(p,n);
            break;


            case 0:
            printf("Exiting...\n");
            exit(0);

            default:
            printf("Invalid Choice!Please Enter Again...\n");
        }
    }

}